DDU of Metered-Dose Inhalers (MDIs)

MDI aerosol characteristics are relatively insensitive to changes in air flow rate because the aerosolisation and dispersion mechanisms are dependent on the force generated by the propellant, rather than the patient’s inspiratory effort. Therefore, for MDIs, the test flow rate is fixed at an arbitrary value of 28.3 L/min. A vacuum pump is used to draw air through the assembled test set-up at this flow rate. However, these test conditions are not applied for DDU testing when the MDI is intended for use with an add-on device such as a spacer or valved holding chamber (VHC).

DDU of Dry Powder Inhalers (DPIs)

Breath-Actuated MDIs (BAIs)

The Breath Actuation Controller BAC 100i can also be used for the testing of Breath-Actuated (or Breath-Operated) MDIs. In this case, the BAC 100i is used to initiate the flow, simultaneously triggering the breath-actuated inhaler.

MDIs: Semi-Automated DDU Testing

The Vertus automated shake, fire and shot waste range is made up of integrated turn-key solutions for precise, controlled and reproducible MDI testing. Compatible with most MDIs, the Vertus systems offer analysts complete control over:

  • The speed, angle and duration of shaking, ahead of actuation
  • Firing force and the speed of application and release of that force
  • The time delay between the end of shaking and device actuation
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Related Applications

We also offer a range of equipment for additional MDI testing application support:

Semi-Automation Tools

Improve efficiency
Reduce variability
Eliminate handling errors
Increase testing capacity

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